Abstract:

With the development of new energy automobile industry,the demand for high energy density power batteries is becoming more and more urgent.The development of high voltage cathode materials and their adaptive electrolytes has become the main research direction in the area of the next generation high energy density power batteries.LiNi_0.5Mn_1.5O₄ is widely concerned for its high voltage up to 4.7 V（vs.Li /Li ⁺）,high energy density up to 650 W·h/kg,abundant resources and low price. However,in the long-term charge and discharge cycles of LiNi_0.5Mn_1.5O₄ materials,Mn dissolves from the electrode materials and damages the electrode materials structure,leading to the deterioration of battery performance.The latest development of LiNi_0.5Mn_1.5O₄ cathode materials and adaptive electrolytes were introduced.The method of ion doping,surface coating and compound is an effective way to improve the electrochemical properties of LiNi_0.5Mn_1.5O₄.At the same time,the high voltage resistance of the electrolytes and LiNi_0.5Mn_1.5O₄ electrodes and electrolytes interface stability can be improved by introducing film forming additives,changing the kinds and concentrations of lithium salt and adjusting formulations of the main types and proportions of solvent.And meanwhile,these methods are also important ways to ascend the battery performance of LiNi_0.5Mn_1.5O₄.Finally,It proposed that the development of 5 V high voltage electrolyte suitable for lithium ion battery was lagging behind,which was the main problem restricting the application of high voltage battery system.

Key words: LiNi_0.5Mn_1.5O₄, ion doping, surface coating, compound method, high voltage electrolytes